** Second update. UPDATE** stay at home mom restrictions..

Okay so I smoked when me and my SO first got together, I ended up quitting because we were ttc.
We now have my son and I had a bad day, ended up smoking a cigarette and wanted another..
My SO tells me I can't buy them because he makes the money and he won't support that. He says the money is for me to decorate the house, get my hair/nails done, etc..
My question is, is this fair? I'm honestly not sure, but I feel like he thinks I'm not contributing to the house hold in any way and I feel a little controlled.. thoughts?
UPDATE* just to make things clear, we both agreed on me being a stay at home mom and I do a damn good job at it. My house is pretty much always spotless, dishes and laundry are always done, dinner is almost always ready for him when he comes home from work, our son is very well taken care of, grocery shopping is always done, and our new puppy is also very well taken care of. & I also have no help what so ever with any of this. Our son has only been watched by someone else a handful of times and he's almost 10 months old. I struggled with post partum depression and thought about suicide daily, not even gonna lie. So yeah, sometimes I just need SOMETHING to help get me through the day. 
We are very financially stable, so cigarettes wouldn't be an issue in that sense. He also wastes so much more money than me, I know that sounds petty but I'm just saying. He could pack his lunch everyday (I actually offered to have it ready for him every single morning) but he would rather eat Mcdonalds every. Single. Day. Real healthy right? Just like my cigarettes? 
I understand the tough love thing but some of these comments were a little ridiculous. I'm a grown woman and if I want to make that decision about my body I think I have the right to. 
If it comes down to it I'll just go out and get a part time job... but I don't think I'm even gonna start smoking again. 
Thanks for all the responses though, it was nice to get some different opinions.
Oh and one more thing, I completely handle all of the finances! If I really wanted to I could go ahead and buy myself cigarettes and he would literally never know but I have more respect for him than that. 
Sorry one more thing, if you guys wanna be technical, I just got my tax return back.. it was $3500 so if I really wanted to spend "my money" on cigarettes, I could. 🙃
Thanks to all of the ladies that shared their opinion without being unnecessarily bitchy. I really appreciate it. Me and my husband talked some more and met in the middle, I got an e cig! Not as smelly and messy. I can't read these comments anymore, a few of them actually hurt my feelings a little bit. I'm a super sensitive person I guess lol.